卫星双向时间比对原理及比对误差估算

论述了卫星双向时间比对原理和比对系统中各项系统误差。计算出同步卫星运动导致的时间延迟误差、地球自转效应(Sagnac)误差和地面站设备时延误差。在所有误差项中，地面站户外单元设备是最大的误差来源，这个值与环境温度是强相关的，且存在反比关系，温度系数达到-0.1ns/℃。对此，可通过温度控制或对数据的温度补偿来降低误差。在对所有误差项进行综合计算后，得出比对误差可低于2ns。

Error Estimation in two-way satellite time transfer

The two-way satellite time transfer(TWSTT) and its systematic errors are discussed in detail, especially the motion of satellite results in time delay errors and Sagnac effect error. About the equipment in stations, such as, transmitter and receiver, main errors come from them, the time delay depends on its ambient temperature. The temperature coefficient is as high as -0.1 ns/℃. Therefore, it is necessary to reduce the error by the temperature control or temperature compensation of the data. At the end, we synthesize the results and obtain the error being less than 2 ns.